I just tuned up my 91 YJ fuel injected 6 cyl ,cap rotor, wires, plugs ( gapped at .035), fuel fllter and wires. Now the engine has a rough idle. the wires are in the correct order and off of idle it runs great. I pulled each wire off with the motor running and they seem to all be working. The fuel filter i took out had the arrow the wrong way and i put the replacement on the right way.... There are no vaccuum leaks that i can see. I also replaced the air filter. and added fuel injector cleaner. there is a little blow by oil on the filter .. What could i have screwed up with the tune up ? Thanks in advance !! Keith

IF you have oil on your air filter, the rear ccv may be plugged. It is the rear vacuum hose fiting that is located on the top rear of the valve cover. The vac line goes from there to a nipple on the intake.If the ccv or the hose is plugged it would cause a rough idle. Pull the vac line and turn the ccv in the valve cover 1/4 turn counter clock wise to remove it for cleanning. Should be able to blow through the ccv and the hose.
Good Luck
Peter